Sean O'Hanlon's header earned MK Dons a 1-0 win at Swindon to push his former club ever closer to League Two.
Centre-half O'Hanlon rose highest to nod home Peter Leven's 16th-minute corner to leave Swindon without a home win in their last 12 games.
On-loan Robins striker Calvin Andrew rattled the crossbar in first-half stoppage time.
Mat Doumbe and O'Hanlon had chances to extend the Dons' lead in the second half before a miserable afternoon for Paul Hart's side was complete when defender Andy Frampton was dismissed 10 minutes from time for a second bookable offence.
The victory keeps MK Dons on course for a play-off place.